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Dead wood dynamics and relationships to biophysical factors, forest history, ownership, and management practices in the Coastal Province of Oregon, USA
Dead wood patterns and dynamics vary with biophysical factors, disturbance history, ownership, and management practices. Through field and modeling studies, I examined the current and potential future amounts of dead wood in two landscapes and region-wide in the Coastal Province of Oregon. The objectives of the first study were to (1) determine whether two landscapes with different recent disturbance histories differ in the amount and characteristics of dead wood; and (2) explore relationships between patterns of dead wood in each landscape to potentially related factors including topography. The objectives of the second study were to (1) describe current regional amounts of dead wood; (2) compare dead wood amounts across ownerships; (3) determine relationships between current dead wood amounts and ownership, current and past vegetation conditions, climate, topography, and soils; and (4) evaluate whether the factors related to dead wood patterns differed according to the scale of analysis. The objectives of the third study were to (1) characterize the projected future change in dead wood amounts in a multi-ownership Province; (2) determine the longevity of present-day dead wood of different types and sizes in relation to amendments from management and stand development; and (3) evaluate differences in management approaches in transitional dynamics and long-term patterns of dead wood. In the first study, I sampled logs and snags at four topographic positions (streams, lower slopes, middle slopes, upper slopes) in the Tillamook State Forest and the Siuslaw National Forest. These two landscapes experienced catastrophic fire at different points in recent history. I developed statistical models relating various attributes of dead wood abundance to biophysical variables related to climate, topography, historical vegetation, current vegetation, soils, and ecoregion. I found that the type and timing of disturbance was important to dead wood amounts and characteristics, and that potential source and sink areas for dead wood were related to topographic position. In particular, lower slopes had higher amounts of logs, and upper slopes had higher basal areas of potential source wood, in the form of snags and legacy (pre-fire) stumps. Climatic factors were of greater relative importance to overall gradients of dead wood in the landscape in which fire occurred less recently. In the second study, I analyzed dead wood data from a region-wide systematic grid of field plots according to ownership and biophysical variables at multiple scales of resolution including plots, subwatersheds. Dead wood abundance and types varied greatly among ownerships, with public lands (Forest Service, Bureau of Land Management, State of Oregon) typically having higher amounts of dead wood and more dead wood in the larger size classes than the private lands (forest industry, non-industrial private). I found that the relative influence of ownership, topography, current and historical vegetation, and climate varied with scale of resolution. Current vegetation was of greater relative importance at finer scales of plots and subwatersheds, whereas climate, topography, and historical vegetation were of greater relative importance at coarser scales of watersheds and subbasins. Ownership was important to overall dead wood gradients at all scales considered. In the third study, by simulating stand development and dead wood dynamics under various forest management scenarios over a 300-year period, I was able to examine the long-term effects of management on dead wood abundance in the Coastal Province. I estimated potential upper bounds for future dead wood amounts. Dead wood amounts increased over time on average across the Province, mainly because of policies on public lands, especially the federal lands under the Northwest Forest Plan. Forest industry, under the Oregon Forest Practices Act and assuming retention of all snags at harvest and thinning, maintained amounts of dead wood that were similar to present-day levels, but size classes shifted toward the smaller sizes as existing large legacy dead wood decomposed. Non-industrial private lands showed increases from very low present-day amounts of dead wood. Across the Province, legacy logs and snags remained present for over a century of the simulation period, and buffered effects of intensive management to dead wood amounts. Variation across landscapes in starting conditions meant that contrasting management approaches had differential effects on long-term dead wood dynamics depending on where they were applied. Current amounts of dead wood and live vegetation patterns in the Province resulted from historical fire and logging. Results of this simulation study indicate that recently established policies oriented toward dead wood production and retention, in the absence of fire or other large- or mid-scale disturbances, are likely to result in increases in dead wood amounts that greatly exceed present-day levels. My results suggest that dead wood patterns of abundance will continue to diverge according to land ownership and that management practices that foster dead wood creation are of increasing importance to the long-term abundance of large dead wood as legacy dead wood is lost through decomposition
Penal Mediation Policy According to Indonesian Criminal Laws to the Protection of Criminal Victims Domestic Violence
Domestic violence is a form of violation of human rights and crimes against humanity, it is also an act of discrimination. This is also regulated in the 1945 Constitution Article 28 G paragraph (1) and Article 28 H paragraph (2) of the 1945 Constitution. In the principle of equality the most fundamental thing of human rights is to place people born free and have equality in human rights, while the principle of violation of discrimination is an important part of the principle of equality. This study examines the problem. There are several obstacles that make it difficult to eradicate domestic violence in Indonesia including the rigidity of law enforcement in enforcing regulations and most are still guided by the Criminal Code even though there are regulations governing domestic violence. And there are some weaknesses in the Criminal Code in handling domestic violence
Smoking and Blindness What Optometrists Want their Patients to See
Most smokers are not aware that their tobacco use is a preventable cause of blindness. Despite the important role optometrists can have impacting patient health choices; their voice has been largely silent in the development of tobacco cessation practice guidelines and health promotion strategies. In this study, we use the International Tobacco Control Policy Evaluation Project (ITC) Four Country Survey to describe the level of Canadian smokers’ knowledge of the association of smoking with blindness and we use focus groups to elicit ideas from Canadian optometrists and senior optometry students about blindness-related graphic warning labels
Impurity state in Haldane gap for S=1 Heisenberg antiferromagnetic chain with bond doping
Using a new impurity density matrix renormalization group scheme, we
establish a reliable picture of how the low lying energy levels of a
Heisenberg antiferromagnetic chain change {\it quantitatively} upon bond
doping. A new impurity state gradually occurs in the Haldane gap as ,
while it appears only if with as . The
system is non-perturbative as . This explains the
appearance of a new state in the Haldane gap in a recent experiment on
YCaBaNiO [J.F. DiTusa, et al., Phys. Rev. Lett. 73 1857(1994)].Comment: 4 pages of uuencoded gzip'd postscrip
Circumbinary disk evolution in the presence of an outer companion star
Stars and planetary system
Le tabagisme et la cécité : ce que les optométristes veulent faire voir à leurs patients
La plupart des fumeurs ne savent pas que le tabagisme constitue une cause évitable de cécité. Même si les optométristes peuvent jouer un rôle important dans les choix santé des patients, ils ont été en grande partie muets dans l’élaboration des guides de pratique sur l’abandon du tabac et les stratégies de promotion de la santé. Au cours de cette étude, nous utilisons l’enquête réalisée dans quatre pays dans le cadre du Projet d’évaluation à l’échelon international des politiques antitabac (ITC) pour décrire dans quelle mesure les fumeurs du Canada connaissent le lien entre le tabagisme et la cécité. Nous utilisons des groupes de discussion pour dégager, chez des optométristes et des étudiants finissants en optométrie du Canada, des idées au sujet de mises en garde illustrées reliées à la cécité
Edge states in Open Antiferromagnetic Heisenberg Chains
In this letter we report our results in investigating edge effects of open
antiferromagnetic Heisenberg spin chains with spin magnitudes
using the density-matrix renormalization group (DMRG) method initiated by
White. For integer spin chains, we find that edge states with spin magnitude
exist, in agreement with Valence-Bond-Solid model picture. For
half-integer spin chains, we find that no edge states exist for spin
chain, but edge state exists in spin chain with , in
agreement with previous conjecture by Ng. Strong finite size effects associated
with spin dimmerization in half-integer spin chains will also be discussed.Comment: 4 pages, RevTeX 3.0, 5 figures in a separate uuencoded postscript
file. Replaced once to enlarge the acknowlegement
Cascade-based attacks on complex networks
We live in a modern world supported by large, complex networks. Examples
range from financial markets to communication and transportation systems. In
many realistic situations the flow of physical quantities in the network, as
characterized by the loads on nodes, is important. We show that for such
networks where loads can redistribute among the nodes, intentional attacks can
lead to a cascade of overload failures, which can in turn cause the entire or a
substantial part of the network to collapse. This is relevant for real-world
networks that possess a highly heterogeneous distribution of loads, such as the
Internet and power grids. We demonstrate that the heterogeneity of these
networks makes them particularly vulnerable to attacks in that a large-scale
cascade may be triggered by disabling a single key node. This brings obvious
concerns on the security of such systems.Comment: 4 pages, 4 figures, Revte
The Haldane gap for the S=2 antiferromagnetic Heisenberg chain revisited
Using the density matrix renormalization group (DMRG) technique, we carry out
a large scale numerical calculation for the S=2 antiferromagnetic Heisenberg
chain. Performing systematic scaling analysis for both the chain length and
the number of optimal states kept in the iterations , the Haldane gap
is estimated accurately as . Our systematic
analysis for the S=2 chains not only ends the controversies arising from
various DMRG calculations and Monte Carlo simulations, but also sheds light on
how to obtain reliable results from the DMRG calculations for other complicated
systems.Comment: 4 pages and 1 figur
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